The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Mar. 20, 1990
Filed:
Jul. 27, 1988
Akira Todo, Ichihara, JP;
Toshio Kimura, Ichihara, JP;
Takeshi Minoda, Ichihara, JP;
Masayoshi Kurisu, Ichihara, JP;
Mitsui Petrochemical Industries, Ltd., Tokyo, JP;
Abstract
A process for producing an information recording disc of an air sandwich structure by ultrasonic welding two disc substrates, at least one of which has a recording medium containing layer, to each other through outer and inner peripheral spacers lying therebetween, which process is characterized in that the outer peripheral spacer is first welded to the disc substrate on one side, the disc substrate on the other side is then superposed through the inner peripheral spacer on said outer peripheral spacer-welded disc substrate turned inside out, and said outer peripheral spacer and disc substrate on the other side, and said inner peripheral spacer and disc substrates on both sides are ultrasonic welded together simultaneously.